I saw on pirate 4x4 some people talking about running late model Toyota pickup leaf springs on the rear of their hardbody. I was wondering if anyone had any info on this because there really aren't many options for aftermarket or lift springs for the hardbody. I think they were talking about 89-97 or so springs.

technically they're both pretty close to the same length i believe, but given the option i'd run jeep xj rear lift springs. The toyota leafs will probably have larger weight capacity but for flex the XJ leafs will be better
Really as long as the leafs are within a workable length you can put any leaf spring in place.

Almost flat is normal for stock. Get some used packs from an XJ or something, lose the thick helper springs, and add the new leaves below the stock Nissan top leaf. Somewhere in the neighborhood of five leaves is a good start.

Using the stock upper leaf maintains the same mounting hardware, and the same center bolt distance. That prevents unforeseen problems with driveshaft length and wheel arch/tire clearance.

Like Syn said, they will flex better, and the ride will be smoother as well.

My lower leaves are from the front of a Wagoneer. The Nissan leaves are in my scrap pile, except for the top ones, of course.

My neighbor had some Land cruiser fj40 leaves im going to try and make work. if not I am gonna get an add a leaf. I had the kind that bolts on the outside of the spring that helped with load but not leveling, If the fj40 leaves dont work Ill be getting an add a leaf for now and I'll look for some xj springs. I am more concerned with capacity rather than flex to be honest. I tend to carry 500 - 1000lb loads often enough to need the capacity

I ended up using fj40 leaf springs that my neighbor had laying around. They were 3 inches wide and I had to notch them a bit with the angle grinder. I took it real slow and cooled off the springs while grinding so they wouldn't lose their temper. I added to my leaf springs right under my overload leaf with a leaf about 24" long. It worked great and now my truck rides great. honestly it was night and day. it takes the load of the camper shell great.